Chimney construction

ABSTRACT

A chimney construction in which single unit blocks stacked about a flue lining are maintained in noncontact relation to minimize heat transfer and eliminate cracking of the structure and including a compressible barrier between the flue lining and the zones within the stacked blocks where reinforced cement grouting is to be poured.

United States Patent Inventors Douglas Luther Hodges 1352 Johnson Ave., San Jose, Calif. 95129; Elwood L. Eberhardt, 275 Leo Ave., San Jose, Calif. 95112 Appl. No. 863,565

Filed Oct. 3, I969 Patented June 1, 1971 CHIMNEY CONSTRUCTION 5 Claims, 4 Drawing Figs.

U.S.Cl 138/114,

Int. Cl E041 17/02 Field of Search 52/218,

210,725; l38/l49, 113, l 14;/98/(Inquired) [56] References Cited UNITED STATES PATENTS 2,076,210 4/1937 Staotfeld 138/113 2,455,570 12/1948 Droeger 52/218 FOREIGN PATENTS 1,083,185 9/1967 Great Britain 138/114 481,290 12/1969 Switzerland 52/725 Primary ExaminerHenry C. Sutherland Attorney-Leslie M. Hansen ABSTRACT: A chimney construction in which single unit blocks stacked about a flue lining are maintained in noncontact relation to minimize heat transfer and eliminate cracking of the structure and including a compressible barrier between the flue lining and the zones within the stacked blocks where reinforced cement grouting is to be poured.

PATENTEI] JUN 1|97l 358177.!

M 5 Fig.2.

w v I bo ugl as Lufber Ho es & Elwood L. Ebe'r/mr Their A/farney CHIMNEY CONSTRUCTION BACKGROUND This invention relates to chimney or stack construction and more particularly to unitary courses and internal air spacing therefor compatible to a flue lining.

Single unit blocks have heretofore been employed in chimney construction as a labor-saving feature for speeding up construction ofa chimney. However, in most cases no internal air spacing sufficient to overcome temperature differentials between the interior and exterior of such single unit blocks has been provided. Such temperature differential causes a differential in expansion and contraction between the interior and exterior of the blocks resulting in development of cracks, ultimate weakening of the stack and faulty operation of the chimney.

THE PRESENT INVENTION The present invention has as its principal object the provision of a stack construction embodying a single unit block for each course, so constructed as to eliminate cracking thereof due to expansion ofits flue lining.

It is another object to provide a single unit chimney block with airgaps so disposed as to dissipate heat from the internal flue lining and minimize the effects of expansion and contraction thereof to the end that development of cracks in the stack will be eliminated.

It is another object to provide a compressible barrier between the flue lining and a reinforced grouted area within the stack facilitating simplicity in construction and noncontact relation between the flue lining and grouted area.

These and other objects and advantages of the present invention will become more apparent from a reading of the following description and claims in the light of the accompanying drawing in which:

FIG. 1 is a perspective view of a fireplace in which a stack embodying the construction in accordance with the present invention is being built;

FIG. 2 is a plan view of the chimney of FIG. 1, but at larger scale;

FIG. 3 is a section through and partial elevation of one unit as shown in FIG. 2 and taken substantially along line 3-3 thereof; and

FIG. 4 is a fragmentary perspective view of a portion of FIGS. 2 and 3.

GENERAL DESCRIPTION Referring to FIG. 1 of the drawing a chimney generally designated is shown as a stack 11 of single unit blocks 12 being built up from a fireplace F. The units 12 are shown being stacked about a flue lining 13 coming up from the throat ofthe fireplace F and as being reinforced by reinforcing rods 14 set into plastic cement between the flue lining and the units [2.

DETAILED DESCRIPTION Referring to FIGS. 2 and 4 the present invention has its embodiment in the configuration of the single block units 12 and the flue lining 13 together with means 15 for isolating the units 12 from the effects of expansion and contraction of the flue lining to thereby overcome the usual effects thereof such as cracking and leakage of fumes from the chimney. To this end each sign single unit block 12 is a molded concrete or bricklike member approximately one brick length (8 inches) in depth and having four sides l6, l7, l8 and 19. The blocks 12 are preferably rectangular in plan as seen in FIG. 2, their longer sides 16 and 18 being approximately half again as long as the end walls 17 and 19. The blocks 12 have an open center adapted to fit over the flue lining l3.

Each of the sidewalls 16 an 18 has an integral internal wall 20 spaced therefrom to provide an airgap 21 at each side of the unit. The internal walls 20 are identical in structure, parallel to the sidewalls l6 and 18 and joined thereto by diagonal webs 22 diverging from center of the block unit 12 to the outer sidewalls. These diagonal webs 22 are connected to the respective sidewalls l6 and 18 approximately one brick width (4 inches) from the adjacent end wall 17 or 19 as the case may be.

The distance between the inner faces 20' ofthe opposite internal walls 20 is slightly greater than width between the outer surfaces of the sides 23 and 23' of the flue lining 13. A spacing of approximately one-eighth inch between the internal walls 20 and the sides 23-23 of the flue lining 13 has been found sufficient to assure against physical contact and heat transfer between them during useofthe flue as a chimney.

The internal area of a flue lining is determined by the size and kind of fireplace or furnace on which the lining is to serve as a chimney. In the drawing a lining 13 for a conventional residential fireplace is shown. Its internal area is approximately 97.75 square inches.

For purposes of the present invention the flue lining 13 preferably has parallel sides 23-23 and curved end walls 24-24. The end walls 24-24 of the flue lining are spaced from the end walls 17 and 19, respectively, a distance to allow for 2 inches of cement between them at the narrowest point. This would be the longitudinal axis of the flue and single unit block 12 as best seen in FIG. 2.

The curved end walls 24-24 of the lining extend as an earlike flange 25 at each end and adjacent the respective sidewall 23-23 of the lining. These earlike flanges 25 are at right angles (normal) relative to the diagonal webs 22 which they face and are spaced therefrom as shown, at least by one-eighth inch clearance. In this connection each of the diagonal webs 22 is provided with an offset shoulder 26 adjacent the earlike flanges 25 and spaced therefrom to assure no direct contact therewith.

A diaphragm 27 of compressible material is disposed over the outer surface of each of the curved end walls 24-24 and latched between the offset shoulders 26 at each of the earlike flanges 25. The compressible material of diaphragm 27 may be corrugated paperboard or any other similar material providing internal air space between outer surfaces. The diaphragm 27 when bowed into place between the offset shoulders 26 act as sleevelike ends into which the sections of flue lining 13 can be slipped during construction ofa chimney.

The arrangement is such that an integral column of cement 28 can be poured into the space C at the ends 17-19 of the single unit blocks 12 ofthe stack. By reason ofthe curved contour ofthe ends 24-24 of the flue lining and the compressible skinlike diaphragm 27 thereon each of the spaces C spread at the corners of the single block unit 12 to provide sufficient thickness, at least 2 inches, of cement around each of the reinforcing bars 14 at the corners.

The chimney 10 thus formed while having the advantage of being easily assembled with unitary blocks 12 also assures of positive alignment of all elements during construction. The internal configuration of the single unit blocks 12 provides a simple means for holding the diaphragms 27 of compressible material without the need of glues, adhesives or additional attaching media. The configuration is such as to provide keyed location of the diaphragms 27 relative to the outer block 12 and to assure for a minimum of space C for the grout or cement by which the blocks are to be united into a monolithic whole. The grout tamped into the spaces C in the usual manner provides maximum strength to the stack with a minimum of cement about the usual reinforcing rods 14. The chimney thus constructed eliminates cracking ofthe stack due to expansion of the flue lining 13. This is due to the spacing of the flue lining from the outer blocks 12 and the airgaps provided by the compressible diaphragms 27 between the cemented ends and the flue lining.

While we have described our improvements in chimney construction in specific detail it will be appreciated by those skilled in the art that the same may be modified, altered and or varied without departing from the spirit or scope of our invention therein as set forth in the appended claims.

What we claim as new and desire to protect by Letters Patent is:

l. For a chimney of the type having single unit blocks adapted to be stacked one upon another about a flue-lining element and to be united by reinforced grouting cement in grouting zones during construction. means for isolating the single unit blocks from the effects of expansion and contraction of such flue-lining element comprising in combination:

a. internal walls formed on and spaced relative to opposite sidewalls of such single unit block and in spaced relation relative to such flue-lining element;

b. each of said internal walls having a shoulder formed at its ends integrally of the respective sidewalls of such single unit block and in spaced relation to the end walls thereof;

c. each flue-lining element including outwardly projecting means adjacent each intersection ofthe end and sidewalls seated on said shoulders and positioning the flue-lining element relative to the surrounding single unit blocks; and

d. a compressible diaphragm disposed adjacent each end of such single unit block with the edges of said diaphragm engaging the shoulders and extending around the ends of the flue-lining element to isolate the latter from the grouting zones at the ends ofsaid single unit blocks.

2. The means for isolating the single unit blocks from the flue lining as in claim 1 in which such flue lining has curved end walls and said projecting means comprising earlike flanges disposed in spaced relation to said shoulders formed at the ends of the internal walls, and in which said compressible diaphragms are bowed to conform to the curved end walls of such flue lining and the edges of said compressible diaphragm have keyed engagement between said earlike flanges and the adjacent shoulder formed on the single unit blocks.

3. The means for isolating the single unit blocks from the flue lining as in claim 1 in which each ofsaid internal walls terminate in diagonal webs diverging toward and at right angles relative to the adjacent shoulder formed on the sidewalls of said single unit blocks.

4. The means for isolating the single unit blocks from the flue lining as in claim 3 in which said flue lining has curved end walls and the compressible diaphragms are bowed in conformance therewith.

5. The means for isolating the single unit blocks from the flue lining as in claim 4 in which said outwardly projecting means comprise earlike flanges at the sides of its curved end walls disposed to extend toward the right angle shoulder and diagonal web for pressing the edges of said compressible diaphragm firmly against the respective shoulders. 

1. For a chimney of the type having single unit blocks adapted to be stacked one upon another about a flue-lining element and to be united by reinforced grouting cement in grouting zones during construction, means for isolating the single unit blocks from the effects of expansion and contraction of such flue-lining element comprising in combination: a. internal walls formed on and spaced relative to opposite sidewalls of such single unit block and in spaced relation relative to such flue-lining element; b. each of said internal walls having a shoulder formed at its ends integrally of the respective sidewalls of such single unit block and in spaced relation to the end walls thereof; c. each flue-lining element including outwardly projecting means adjacent each intersection of the end and sidewalls seated on said shoulders and positioning the flue-lining element relative to the surrounding single unit blocks; and d. a compressible diaphragm disposed adjacent each end of such single unit block with the edges of said diaphragm engaging the shoulders and extending around the ends of the flue-lining element to isolate the latter from the grouting zones at the ends of said single unit blocks.
 2. The means for isolating the single unit blocks from the flue lining as in claim 1 in which such flue lining has curved end walls and said projecting means comprising earlike flanges disposed in spaced relation to said shoulders formed at the ends of the internal walls, and in which said compressible diaphragms are bowed to conform to the curved end walls of such flue lining and the edges of said compressible diaphragm have keyed engagement between said earlike flanges and the adjacent shoulder formed on the single unit blocks.
 3. The means for isolating the single unit blocks from the flue lining as in claim 1 in which each of said internal walls terminate in diagonal webs diverging toward and at right angles relative to the adjacent shoulder formed on the sidewalls of said single unit blocks.
 4. The means for isolating the single unit blocks from the flue lining as in claim 3 in which said flue lining has curved end walls and the compressible diaphragms are bowed in conformance therewith.
 5. The means for isolating the single unit blocks from the flue lining as in claim 4 in which said outwardly projecting means comprise earlike flanges at the sides of its curved end walls disposed to extend toward the right angle shoulder and diagonal web for pressing the edges of said compressible diaphragm firmly against the respective shoulders. 